Rather than joy and excitement, the unearthing of what an academic called "a Byzantine Pompeii" at the heart of modern day Thessaloniki, Greece's second city, has caused bitter controversy in a country clutching at economic straws.

Instead of sealing off the ruins, the backers of a key rail project being built at the same site are threatening to have them removed within weeks.

Six metres below ground, archaeologists found what they say exceeded even their wildest dreams: the commercial heart of the ancient city below the commercial heart of the modern one - marked by a crossroads built by Caesar Galerius in the 4th Century and reconstructed two centuries later, when Thessaloniki had become the second city not of a nation-state, but of the multinational Byzantine Empire.

Descending the staircase to reach the closed-to-the-public dig site, you can see an incredibly well-preserved marble-paved road, complete with the remains of what used to be shops, workshops and public buildings and spaces. The road is still visibly etched by the passing of carriages, while the accompanying archaeologist even points to a marble block showing the markings of a noughts-and-crosses game, presumably carved by children playing in the open air market 17 centuries earlier.

Archaeologists and city authorities dream of a metro station combined with a subterranean museum, that will become a major tourist attraction and a constant reminder of the city's glorious past - a past lamentably hidden today by decades of anarchical construction and disastrous city planning.